it's the last one because it's depended on the rock layers
Answer:
pH = 4
Solution is acidic
Explanation:
Given data;
Hydronium ion concentration = 1 × 10⁻⁴ M
pH of solution = ?
Solution:
pH = -log [H₃O⁺]
pH = -log [ 1 × 10⁻⁴ ]
pH = 4
According to pH scale the pH 7 is neutral while the pH less than 7 is acidic and greater than 7 is basic. The given solution has pH 4 it means solution is acidic.
Answer:
Mass = 0.37 g
Explanation:
Given data:
Number of moles of sulfur = 11.9 mol
Mass of sulfur in 11.9 mol = ?
Molar mass of sulfur = 32.06 g
Solution:
Number of moles = mass/molar mass
by putting values,
11.9 mol = mass/ 32.06 g/mol
Mass = 11.9 mol × 32.06 g/mol
Mass = 0.37 g
Answer : The fuel value and the fuel density of pentane is, 49.09 kJ/g and
respectively.
Explanation :
Fuel value : It is defined as the amount of energy released from the combustion of hydrocarbon fuels. The fuel value always in positive and in kilojoule per gram (kJ/g).
As we are given that:

Fuel value = 
Molar mass of pentane = 72 g/mol
Fuel value = 
Fuel value = 49.09 kJ/g
Now we have to calculate the fuel density of pentane.
Fuel density = Fuel value × Density
Fuel density = (49.09 kJ/g) × (0.626g/mL)
Fuel density = 30.73 kJ/mL = 
Thus, the fuel density of pentane is 